[Ga₂Cl₄(dioxane)₂]_x: molecular structure and reactivity of a polymeric gallium(II) halide containing two five-coordinate gallium atoms about a Ga–Ga bond

Abstract

A polymeric 1,4-dioxane adduct of gallium(II) chloride, [Ga₂Cl₄(dioxane)₂]_x, containing two five-coordinate gallium atoms about a Ga–Ga bond [Ga–Ga 2.3825(9) Å], reacts with 1,4-dilithiotetraphenylbutadiene affording an unusual Ga(II)–tetraphenylbutadiene complex.

References

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4. Inside the drybox (M. Braun Labmaster130) Ga₂Cl₄(Aldrich Chemical Co.)(17.8 mmol, 5 g) was dissolved in 1,4-dioxane (25 mL). The resulting mixture was filtered and the solution was allowed to stand at room temperature for several days resulting in colorless cubic crystals (4 g, 62% yield). Mp 158–159 °C. Anal. (E + R Microanalytical Laboratories, Parispanny, NY) Calc. (found) Ga₂Cl₄(dioxane)₂: C, 21.00 (21.17); H, 3.50 (2.90%). The less than ideal hydrogen analysis may be due to the loosely associated solvent molecules. ¹H NMR (300 MHz, 298 K, THF-d₈): δ 3.52 (m, 2H, –OCH₂); ¹³C NMR (300 MHz, 298 K, THF-d₈): δ72.7 (–OCH₂).
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